QML Data Model and columns



  • I started to port a QWidget application to QML. I'm slowed down by QWidgets use of Columns and QML's use of roles from QAbstractItemModel. After searching the problem, "QMLifyProxyModel":http://www.qtcentre.org/wiki/index.php?title=QMLifyProxyModel was found. I haven't tested out the solution, however I'm wondering what was the reasoning for using columns with QWidget and Roles in the QML world?

    By QWidget I mean specifically QTableWidget.

    Also, It looks like QMLifyProxyModel was updated 1 1/2 years ago. I would like to know if there is a better solution to bridge a column based model to a role based model.



  • The widget world also uses roles. The problem is that qml views only work with list-type models at present so roles find a greater use for more freedom.

    Please feel free to get involved and write some more versatile qml views that can be used with table or even tree-like models.

    I will be very interested to see what solutions you come up with for this problem.



  • Thanks for the response, I'll look into making a QML table view. Do you know of any benefit of using Columns instead of Roles? Besides being compatible with a QTableWidget.



  • Before you start from scratch, let me point to the Desktop Components project. It already supports a table view with columns, but indeed, it is based on rows.

    From a design perspective, I get that using roles may be the better design for many situations. Often (not always), the items on a single row in a table really just represent aspects of a single underlying item. For instance, if you are displaying contacts, all the items in the columns (name, d.o.b., phone number) represent aspects or attributes of a single entity: the person. That makes it logical to be able to treat them as such. Representing such information as a table model, pre-supposes that you want to display such information always in a table form. That may not be the case. Perhaps you want to use a representation that looks like a set of business cards instead, for instance. Having the model in the form of a table would then be harder to use. Using a table to represent objects with a number of attributes is one way to represent them, but not the only way.


Log in to reply
 

Looks like your connection to Qt Forum was lost, please wait while we try to reconnect.